Student team's robot safely detects land mines

PORTLAND, Ore.  Johns Hopkins University engineering students recently completed a remote-controlled robot that can find land mines in rugged terrain and mark their location by spraying paint.

"I challenged the students to develop a vehicle that could get into rougher terrain, like bushes and high grass," said Carl Nelson, a principal staff physicist at the university's Applied Physics Laboratory. "I wanted it to be able to get off the roads and clear paths  where mine detection can be difficult to do by hand."

Four Johns Hopkins engineering students rose to the challenge and spent almost a year designing a prototype robot. The machine is being evaluated by explosive-detection experts as a model for a low-cost robot for soldiers and humanitarian groups. It was designed by engineering students Edoardo Biancheri, Dan Hake, Dat Truong and Landon Unninayar. The project encompassed a two-semester course called the Engineering Design Project.

Nelson was working on advanced sensor designs for the military, but needed something to carry them into deep grass and other areas that typically are difficult to scan for mines. Because every year the Applied Physics Laboratory sponsors, with funds and ideas, at least one of the "Engineering Design Project" teams, Nelson decided to ask one of them to come up with a solution.

Safe and inexpensive

The problem with land mines worldwide is not along roads, where they can be easily found and destroyed. The main danger is in areas of thick vegetation where they are often hidden, making them almost impossible to detect without setting them off.

The United Nations estimates, according to Nelson, that 2,000 people per month are killed or maimed by land mines, and that more than 100 million mines have been deployed in 70 countries during military conflicts dating back to World War II.

Nelson said he was looking for solutions that could safely and inexpensively locate and neutralize land mines when he challenged the students.

The engineering students designed a tracked vehicle  like two tandem knee-high tanks. The first vehicle houses the sealed lead-acid battery, two electric motors for the treads, the radio-controlled transceiver and a color video camera. A display allows the operator to peer down at objects in front of the vehicle and up to 100 feet away.

The second unit houses the mine detection equipment and also enables the total weight of the vehicle to be distributed enough to make it very light, making it less likely that it will set off mines. Likewise, as much metal as possible has been replaced with plastic and composites in the vehicle so that any metal detected comes from mines and not the vehicle itself.

The rear unit is also equipped with a paint storage tank and a nozzle that enables it to paint the locations of up to 40 land mines before returning to base for more paint.

The radio-controlled transceiver, which can be used up to 500 feet away, allows the vehicle and its video camera to be steered by standard joysticks. The video camera presents a live feed to a small video screen built right into the joystick controller. In the prototype, the metal detector produced a beep on the controller whenever it was over a land mine. In response, an operator can activate the paint sprayer to mark the spot.

The students were given a budget of $8,000 but they only spent $5,000 to design and build their prototype. They estimate that production versions could cost as little as $1,000.

Eight other teams were funded this year under the "Engineering Design Project" course at Johns Hopkins. The course is taught by professor Andrew Conn, a Johns Hopkins graduate with more than 30 years of experience in research and development. Each team had budgets of under $10,000, supplied by government agencies and the private sector, to manufacture or buy the parts, assemble them and demonstrate the prescribed function being performed.

Nelson is currently outfitting the robot for demonstration to the military, which is slated to review it later this year.